Heart Attack : Causes and Risk Factors

by National Institute on Aging

(Page 2 of 5)

Most heart attacks are caused by a blood clot that blocks one of the coronary arteries, the blood vessels that bring blood and oxygen to the heart muscle. When blood cannot reach part of your heart, that area starves for oxygen. If the blockage continues long enough, cells in the affected area die.

Coronary artery disease is the most common underlying cause of a heart attack. Coronary artery disease is the hardening and narrowing of the coronary arteries caused by the buildup of plaque inside the walls of the arteries. Over time, the buildup of plaque can

• narrow the arteries so that less blood flows to the heart muscle,
• completely block the arteries and flow of blood, or
• cause blood clots to form and block the arteries.

A less common cause of heart attacks is a severe spasm or tightening of the coronary artery that cuts off blood flow to the heart. These spasms can occur in persons with or without coronary artery disease. Artery spasm can sometimes be caused by emotional stress, exposure to cold, cigarette smoking, or by taking certain drugs like cocaine.

Certain factors make it more likely that you will develop coronary artery disease and have a heart attack. These risk factors include some things you cannot change. If you are a man over age 45 or a woman over age 55 you are at greater risk. Having a family history of early heart disease, diagnosed in a father or brother before age 55 or in a mother or sister before age 65 is another risk factor. You are also at risk if you have a personal history of angina or previous heart attack, or if you have had a heart procedure such as angioplasty or heart bypass.

Importantly, there are many risk factors that you can change. These include

• smoking
• obesity
• physical inactivity
• high blood pressure
• high blood cholesterol
• diabetes

You can help prevent a heart attack by knowing about your risk factors for coronary artery disease and heart attack and taking action to lower your risks.

You can lower your risk of having a heart attack, even if you have already had a heart attack or have been told that your chances of having a heart attack are high. To prevent a heart attack, you will need to make lifestyle changes. You may also need to get treatment for conditions that raise your risk.

You can make lifestyle changes to lower your risk of having a heart attack.

• Eat a healthy diet to prevent or reduce high blood pressure and high blood cholesterol, and to maintain a healthy weight.
• If you smoke, quit.
• Exercise as directed by your doctor.
• If you are obese or overweight, lose weight gradually.

Get treatment for related conditions that might make having a heart attack more likely. If you have high blood cholesterol, follow your doctor's advice about lowering it. Take medications to lower your cholesterol as directed.

Get treatment for related conditions that might make having a heart attack more likely.

• If you have high blood pressure, follow your doctor's advice about keeping it under control. Take blood pressure medications as directed.
• If you have diabetes, sometimes called high blood sugar, follow your doctor's advice about keeping blood sugar levels under control. Take your medicines as directed.

Quiz

1. If you are at risk for heart disease, there is little you can do to change your risk.

FALSE is the correct answer. There are many things you can do to reduce your risk of heart disease. Stop smoking, increase physical activity, lose weight, and control diabetes, high blood pressure, and high blood cholesterol.

2. Heart attacks are usually caused by underlying coronary artery disease.

TRUE is the correct answer. Coronary artery disease is the most common underlying cause of heart attacks. It is the hardening and narrowing of the coronary arteries caused by the buildup of plaque inside the walls of the arteries.

3. Many other health conditions can increase your risk of heart attack.

TRUE is the correct answer. High blood cholesterol, high blood pressure, and diabetes can all increase the risk of heart attack.

4. Women are not at risk for heart attack.

FALSE is the correct answer. About half of all heart attacks occur in women, and the risk for women increases after age 55.

About the Author

www.nia.nih.gov
NIA, one of the 27 Institutes and Centers of NIH, leads a broad scientific effort to understand the nature of aging and to extend the healthy, active years of life. In 1974, Congress granted authority to form NIA to provide leadership in aging research, training, health information dissemination, and other programs relevant to aging and older people.